Table 1.
List of species and the number of specimens from which at least a partial COI sequence was recovered.
Abbreviations for the countries of origin: B–Belgium, CH–Switzerland, DE–Germany, E–Spain, F–France, FIN–Finland, GB–Great Britain, GR–Greece, I–Italy, NL–The Netherlands, RUS–Russia, SE–Sweden. Singleton countries are written in full. Length of the longest COI sequence together with the number of ambiguous bases is indicated. The list follows the taxonomic order of Herting & Dely-Draskovitz [29].
Fig 1.
Overview of the tachinids sequenced in the FinBoL project.
(A) Accumulation curve for the 366 species, corresponding 329 BINs. (B) The FinBoL project produced DNA barcodes for 280 Finnish tachinid species (85% of the species recorded in Finland) and for 86 non-Finnish species, which most are present in the adjacent countries. No samples or successful barcodes were obtained for 48 species on the Finnish checklist. Example species: Female Carcelia bombylans Robineau-Desvoidy, Espoo, Finland.
Fig 2.
Examples of species or species complexes with poor BIN separation.
(A) Exorista mimula (Meigen) COI sequence is embedded within the E. rustica (Fallén) sequences in the NJ trees. Same applies to E. fasciata (Fallén) and E. larvarum (L.), whereas similarly closely related E. grandis (Zetterstedt) and E. sorbillans (Wiedemann) are distinctly different. Notice also the differentiation between the Finnish and the Mediterranean specimens of E. deligata Pandelle. (B) Whereas E. mimula and E. rustica can be reliably determined only using male genital characters, E. fasciata (upper) and E. larvarum (lower) are clearly separable by various morphological characters and habitat preference. Other morphologically distinct species sharing BINs are (C) Eumea linearicornis (Zetterstedt) and E. mitis (Meigen), Nilea hortulana (Meigen) and N. innoxia Robineau-Desvoidy, (D) Gymnosoma spp. (E) Macquartia dispar (Fallén) and M. viridiana Robineau-Desvoidy as well as (F) Leucostoma spp. Scale bar: 2% sequence difference.
Fig 3.
NJ tree of Siphona COI sequences.
Contrary to the expectations, BINs have a good resolution in this morphologically variable genus, whose members are notoriously challenging to determine, only expectation is the S. collini Mesnil–S. maculata Staeger pair. Some duplicates omitted from the NJ tree for clarity, see S2 and S3 Figs for the full data. Example species: Male Siphona setosa Mesnil, Jämijärvi, Finland.
Fig 4.
Geographic variation in tachinid COI sequences.
(A) The northern Finnish (map locations 1–2) Microsoma exiguum (Meigen) belong to a different BIN cluster than the specimens from southern Finland, Central Europe (map locations 3–6) and Mediterranean France (map location 7). Note that the specimens from Provence represent a different haplogroup than the Central European ones, although the difference is not enough to split the BIN. Similar differentiation was not observed for (B) Tachina fera (L.), (C) Mintho rufiventris (Fallén), Thriarthria setipennis (Fallén) and (D) Cylindromyia brassicaria (Fabricius) collected from the same locations. Example species: Male Microsoma exiguum, Friedberg, Germany. Scale bar: 1% sequence difference.
Fig 5.
Intraspecific BIN splits in Finnish Tachinidae.
(A) Finnish Gymnocheta viridis (Fallén) are split into two separate BIN clusters with a minimum divergence of 1.41% between them and a maximum divergence of 0.62% within the clusters. The G. sp. nr. viridis is also ecologically separable from the true G. viridis with all records being solely from the northern and eastern Finnish bog habitats, whereas the latter is almost purely a meadow species. (B) The Finnish Medina collaris (Fallén) specimens are similarly falling into two separate BINs. Coincidentally to G. viridis example also M. sp. nr. collaris are confined to bog habitats. Both Medina species have one rear bristle on their forelegs, a character state not present in other European representative of the genera. Example species: Male Gymnosoma sp. nr. viridis, Lieksa, Finland. Scale bar: 1% sequence difference.
Fig 6.
Possible taxonomic conflicts within tachinid genera.
(A) Kirbya moerens (Meigen) is embedded within the COI sequences of the closely related Wagneria, whereas the other Voriini genera form their own clusters. Voria is thought only to be represented by V. ruralis (Fallén) in the Palearctic. However, the COI of a specimen from S-Agean Greece differs significantly (by 4.91%) from the northern European examples and could represent a species of its own. Similar to Kirbya–Wagneria case, also (B) Billaea–Dinera and (C) Phorocera–Parasetigena have mixed COI clusters. Example species: Male Billaea kolomyetzi, Ruokolahti, Finland. Scale bar: 2% sequence difference.
Fig 7.
Deep divergence within tachinid genera.
(A) COI from Oswaldia reducta (Villeneuve) has more sequence similarity with genera other than Oswaldia. (B) Species of Phebellia fall into two distantly related clusters, which also do not represent the proposed split of the genus into Phebellia s. str. and Prooppia [45].